The Angels center fielder scorched a solo homer that sailed into the second set of fountains in left-center at Kauffman Stadium, which sit adjacent to the scoreboard in dead center, putting his team on the board and dropping jaws in both dugouts.

Angels manager Mike Scioscia said it's "about as far as you're going to see a ball hit," and at least one estimate agrees with him.

Royals media relations estimated it at 445 feet, but ESPN's Home Run Tracker had it at 489 feet, which would mark the longest home run this season and the longest of Trout's career. The latter distance is the longest home run since Marlins right fielder Giancarlo Stanton hit one 494 feet on Aug. 17, 2012, and the longest by an American League player since ESPN began tracking home runs in 2006.

One reason for the discrepancy in the two estimates might be the fact that ESPN's Home Run Tracker measures "true distance," which is how far the ball would have traveled if unimpeded.

"I definitely barreled it," Trout said after the Angels' 8-6 loss. "I just tried to put a good swing on it. I got a pitch I could hit and hit it out."

Trout's second-longest homer -- 461 feet on May 23, 2013 -- also came at Kauffman Stadium against a former teammate in Ervin Santana.

Since entering the Majors in 2011, Trout has ranked third in average distance of homers. His 415.2 feet trail only the Braves' Justin Upton (418.2) and Stanton (416.2). Per ESPN, Friday's blast was the longest homer at Kauffman Stadium since at least '06, surpassing Travis Hafner's 481-foot shot on April 15, 2012.

"Well, I've been here five years and that's the most impressive home run I've seen here," Royals manager Ned Yost said. "I mean, it was just absolutely crushed."

Trout sports a team-leading 18 home runs, tied for fifth in the AL, and ranks second in the Majors with a 1.019 OPS. But he has yet to be invited to the Home Run Derby by AL captain Jose Bautista.